<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>

  <style>
    body {
      height: 100vh;
      display: flex;
      align-items: center;
      justify-content: center;
    }

    main {
      display: flex;
      gap: 20px;
    }

    .circle {
      width: 30px;
      height: 30px;
      background-color: skyblue;
      border-radius: 50%;
      animation: move 1s infinite;
    }

    .circle:nth-child(1) {
      animation-delay: 0.1s;
    }
    .circle:nth-child(2) {
      animation-delay: 0.2s;

    }
    .circle:nth-child(3) {
      animation-delay: 0.3s;

    }


    @keyframes move {
      0% {
        transform: translateY(0px) scale(1);
        background-color: #7481fb;
      }
      50% {
        transform: translateY(50px) scale(.4);
        background-color: skyblue;

      }
      100% {
        transform: translateY(0px) scale(1);
        background-color: #7481fb;
      }
    }
  </style>
</head>
<body>
  <main>
    <div class="circle"></div>
    <div class="circle"></div>
    <div class="circle"></div>
  </main>
</body>
</html>